Sennheiser Consumer Audio HD 660S2 – Wired Audiophile Stereo Headphones with Deep Sub Bass, Optimized Surround, Transducer Airflow, Vented Magnet System and Voice Coil – Black

Product Description:

From the brand

We are audio experts and music lovers who’ve been striving for the best audio experience. Through the craft and precision of German Engineering we create innovative products to reinvent the future of audio with remarkable audio experiences that you don’t just hear – but feel. That is what the Sennheiser brand has represented for more than 75 years.

Intense Science

We are driven by the passion to create audio solutions that make a difference, by constantly rediscovering the needs of our customers.

Intense Sound

Our ability to redefine sound has continued to set the norm, allowing music lovers worldwide to experience sound in a new dimension.

Intense Emotion

As audio fanatics we strive for a remarkable sound you not only hear – but feel. We measure our success by the goosebumps on your skin.

We invite you to discover our wide variety of premium audio products, which are divided into the following four categories: Premium Headphones, Audiophile Headphones, Hearing Solutions and Soundbars.

Premium Headphones

Offering a wide selection of headphone styles from True Wireless to Over-Ear for premium music enjoyment no matter where you are.

Audiophile Headphones

Continuously striving to define new industry standards with headphones for both home and mobile listening.

Hearing Solutions

Seeking to provide market-leading enhanced hearing products​ from TV listening to situational hearing.

Soundbars

Providing outstanding immersive sound experiences for home entertainment by a single device.

Hear the Difference

Natural, relaxed, high-fidelity sound with extra sub bass: Ultra-light aluminum voice coil with 300-ohm impedance for excellent impulse response and an intimate sound with great timbre
Airflow-optimised 42mm high-performance transducers: Improved ventilation due to a uniquely powerful vented magnet system for minimal distortion and air displacement control through steel mesh damping
Double the sound pressure at the lowest octaves: You can feel the lowest note on the piano (27.5 Hz) or the kick of the bass drum (45-60 Hz) as if you were there, at the recording studio
Exceptional comfort and build quality: The open-back design offers exceptional breathability and the plush ear cushions deliver maximum comfort – for long listening sessions
Outstanding quality designed in Germany, made in Ireland: With a frequency response of 8 Hz – 41,500 Hz and detachable, long cables for comfortable desktop use

Product Summary:

Item Details:

Products Reviews:

Reviewer: Frank Doghearty
Rating: 5.0 out of 5 stars
Title: It’s magic: enter the concert hall
Review: Update on August 9, 2024:The iFi DAC combined with the iFi Zen Can produced clear sound and proper dynamics, but human voice sounded feeble and harmonics were missing (that is, a concert piano sounded like an electronic one).I figured it was the amplifier, not the headphones, so I gave a try to an XDUOO TA-10R, which is a hybrid headphone amp, using a balanced tube and Class A amplification (USB, optical, RCA, and coax inputs, a pseudo-balanced output that still sounds better than the 6.3mm unbalanced one). Once I swapped out the factory tube for a Gold Lion, the sound stage opened up, human voice became full, and the harshness around the high C vanished. Even poor recordings (uncompressed) sound good, providing a lot more presence than I experienced from the iFi combo. The fullest sound that goes deepest uses a Tungsram tube.I must admit that a $40 Koss would probably meet most people’s need.Also, as my old friend said about 50 years ago, no headphone can compete with a good room setup (which can be hilariously expensive, but not necessarily. Compiling it from used items, you can get one for around $10k, which is still a lot less than the top-of-the-line headphones that still can’t compete with it.Original review from May 24, 2024:Every time I put them on, I feel mesmerized. Have never had this experience with any other headphones; it’s like the music comes to life around my head, as if I was present at the performance. Granted, that applies mostly to classical music, and the sound can easily bring tears into my eyes.Still, these babies produce excellent sound for everything I’ve put on them. I’m not a gamer, so I can’t comment on the gaming performance, but there is at least one 5-star review on that subject.Anyway, beyond the subjective, sources and recordings are also essential to consider as well as the connections, so let me submerge into those details.Good headphones are no good for compressed sound, but plenty of headphones are made for such a clientele. The s2 with its refined sound is targeting an audience that cares for the original sound.Please, notice that when people “burn in” new equipment, during much of that (except for diaphragms in speakers), what happens is that the components adjust to each other, especially on the analogue side. The outcome ultimately determines if their combination is feasible or not. My current setup has been serving me well in the last five years or so, so I haven’t made any changes.I used an iFi Zen DAC v1 (from the USB port on computer) and an iFi Zen Can v1 (on the RCA input from a relatively high-end LG Blu Ray player from the optical port through a digital-to-analogue converter). Connected the DAC with the amp through their balanced ports with a short decent balanced cable. Both amps were hooked up to the sources with SVS interconnect cables. Didn’t use the “Trubass” feature on either one, because for my taste, it upsets the sound balance (the DAC also amps the bass at a higher frequency than the amp). My sources were the usual high-resolution recordings (both pop and classical) and Blu Ray movies I use for testing new components.The most prominent strengths of the s2 is extended bass and an adherence to the original sound signature. While the OEM cables are fine, out of the two supplied, I favor balanced one. I have found a purchase for a previous Sennheiser that didn’t work out at the time giving me better resolution. Amazon is still selling it: KK Cable II-SO. (Added on 6/28/24: for movies, the original balanced cable works better; the KK produces less bass in return for better instrument positioning, and dialogues suffer from human voice being elevated around 500Hz, which makes conversations harsh and unpleasant to listen to. The original cable goes deeper, although perhaps a bit muddied in the lowest end, but conversations are clear). The only problem with the extended bass is that the housing loses a little control over it beyond a certain (obviously VERY high) volume, so I can sort of feel the ear cups moving, which breaks the illusion of being present. This is probably the main reason why the pressure around the ears is relatively high (and loosening it might not be the best idea).The s2 might not be the best for someone with a large head (it might feel uncomfortably tight) or unusually large ears that the ear cups cannot cover, and it took me a few days to get used to it, because I am on the high end of average head and ear sizes.The included bag is a plastic dust collector; I am using an anti-static bag instead. Hard cases are available for transportation, but the original box works for that, if only on occasion.As opposed to the planars I’ve heard (Moondrop Para and Hifiman HE400se, but others report the same problems with lot costlier planars), the s2 retains the familiar sound on the recordings I usually use for testing new equipment, and it extends the listening experience in gentle, but important ways. The bass reverberates in the concert hall, and is not victim to extensive channel separation. Even harmonics play the same or better than on anything else I’ve heard in this price range or below, although this is a feature that can warrant higher investments. No problem with high-pitched human voice being harsh and sibilants don’t suppress other frequencies; the performance is actually toned down a bit in order to retain the sound that recordings must have been meant to sound like. In my understanding “warm sound” is often used for describing the feature, perhaps because no highs and mids dominate at the expense of the bass or each other. Despite the somewhat reserved (but not veiled) presentation, the dynamics don’t suffer.I believe, the secret is ingenious engineering that uses physics: the proper driver and built-in sound paths in the earphones. Many other headphones have built-in electronics in the sound path, allegedly, to protect the user’s hearing, but to me, it seems more like protecting the drivers from overload. Consequently, the s2 doesn’t clip at low bass (emit a clicking sound, while cutting out the sound), while most the sound is there in that region, too. The headroom is like sitting in the concert hall, albeit a bit further in the back that the eight row, but the sound image remains steady at various volume levels. To me, the harmony and the unity of the sound, along with the original sound signature, is worth the price.Added on 04/03/25:The best cable I’ve found for these is https://www.amazon.com/gp/product/B0BZMS68RV, although it lasted only for six months. The best amplifier in this price range is a hybrid tube (the tube is only for buffering a Class A headphone amp) is the XDUOO TA-10R.
Reviewer: Dylan B.
Rating: 5.0 out of 5 stars
Title: Insane sound quality, detail, and bass output – Great for immersive video games
Review: Quite a few people will say these headphones aren’t great for gaming. Ignore those clowns.Video Games: 10/10The issue is that 95% of headphone reviewers when asked “what makes a good pair of headphones for gaming” – almost exclusively look for the widest soundstage possible and super clear treble. Which I mean, is great for pinpointing footsteps. But there are people out there who play more than just FPS games. If you’re a solely hyper-competitive FPS gamer, maybe something from the Hifiman/Beyerdynamic lineup is better for you. But I would recommend these cans for everything else.If you play any games that are immersive in nature or are known to have good sound quality, such as Cyberpunk 2077, Elite Dangerous, or Elden Ring. You will love these headphones. But, even in games like Rainbow Six Siege, I didn’t perceive any noticeable drop in my perception of where people were compared to my old cans which were the HD598 CS. In fact, that aspect is pretty much the same, and hearing gunshots and explosions in Rainbow Six was pretty jaw dropping as well. You can hear the rumble of an impact grenade from the other side of the map sort of bellow in your ears. The low/deep growl of a deagle firing off sounded impressive as well. I did EQ mine on the low-end to output some nice rumble.Cyberpunk 2077 was easily the game that blew me away the most. It legitimately sounded like a different game to me – it’s THAT drastic of a difference. I heard things I hadn’t heard before – as if this is how the game was MEANT to sound. It literally makes me feel like I’m there when I hear cars rumble past me on the street, and I think it’s as close to life like as you can get from a pair of headphones. In another instance, there was a highway above me and surrounding me was a market full of people talking, in game music (like from radios), advertisements, etc – and I feel like I’m standing there, in the market. Imagine the cars from above encompassing your entire soundstage in the background, like further away, but the details of the market still sound closer and don’t lose their detail.Music: 9/10For music, there’s plenty of other reviews that cover that, but these don’t disappoint. I mainly listen to video game OSTs, rock bands like Cage the Elephant, or metal like Sabaton. Definitely an improvement over my old 598 CS.Movies: 8/10I haven’t tested these out with movies/TV shows too much so I can’t give a fair opinion on that, but so far they sound good, nothing yet that has super impressed me.Comfort: 9/10These feel fantastic, some people claim the clamp force is too tight, but it feels just right on my normal sized head with normal sized ears. They might feel a bit tiring to wear for prolonged periods, but supposedly this will subside with time.Overall: 9/10I am truly impressed by these headphones. The details, bass, sound quality, and imaging capabilities of these blew me away. Easily worth $400 on sale. If anything, it makes me appreciate the source of audio I am hearing more. For example, I can more easily tell if a game had a higher quality audio team working on it, or if a song was produced in a studio vs some trash recording.Sidenote:I am someone who likes emphasized bass, neutral mids, and neutral treble. I find emphasized treble to be annoying and shrill to listen to. I was also that kid in high school who would have to cover their ears completely during fire drills (and it seemed like I was the only one) – so if that sounds like you then you probably have the same tonality preferences as me. I also tested these with a Fiio K7 and Fiio E10K as my amp/dac sources.
Reviewer: Ryan G.
Rating: 5.0 out of 5 stars
Title: I love these headphones
Review: I am very picky about my headphones, but I have come to find the Sennheiser sound profile to be the best one for me. I am not an audiophile, but these sound exceptional to me.The 660S2’s are lightweight and very comfortable to wear. They fit firmly on my head (with a bit too much clamping force out-of-the-box; they can be safely stretched out) and I’ve had no issues wearing them for extended periods of time.They look fantastic. Part of the reason I chose these over the 660’s or the Massdrop x Sennheisers was the copper touches on the flat black frame. Granted, I got them for a much more competitive price than $600 (more than half of that), but the aesthetics speak to me a lot.For everything I’ve listened to with them, I have has no issues. No buzzing, no crunchy audio. It sounds smooth and clear regardless of the genre. I’m not someone who needs to have all of the bass, but it delivers high, medium, and low frequencies without hurting my ears or sounding off.I’m so happy with these. For the price, it delivers comfortable home listening (through my phone or my turntable) and the open back nature truly broadens the soundstage beyond what noise cancelling headphones can ever deliver. I recommend doing your homework on these and check out various comparisons if you can’t try these out in person, but I think these will make a lot of prospective buyers very happy.
Reviewer: Veca
Rating: 5.0 out of 5 stars
Title:
Review: Son exceptionnel
Reviewer: Natural Music Studio
Rating: 5.0 out of 5 stars
Title:
Review: Perfeito, chegou antes do prazo. Não veio com a nota fiscal pois é comprado nos EUA, e entregue como pessoa física, por isso o preço está abaixo do site oficial. Também é não recebi a nota fiscal da loja …
Reviewer: PCH
Rating: 2.0 out of 5 stars
Title:
Review: Well…a few hours in and let’s say I am not overwhelmed. Very little difference between these and XM5s and maybe not so good. Returning.
Reviewer: Amazon Customer
Rating: 5.0 out of 5 stars
Title:
Review: Ok.The Skinny of it…A little rough in the edges but..still acceptable by listening standard.Compared to AT WP 900 this model is on the softer side and rougher on the highs.Compared to Grado SR60 the sound is compressed with this headphone.Compared to Sony MZR 2 the 1k version that is opened and not compress but you feel you want to play it louder. But no complains if you want to pamper yourself.Finally compared to the top of the line Focal 6k model. This one is bar none. Dynamics highs mid and tonal separation this is serious stuff. But Seriously all running on the same LG V60 as source with Tidal and with USB audio pro meaning it is forced to output 16bit. Not 48….Final word for the price…we have to be fair for the quality of sound on the price. If you were to compare it with the AT WP900 same price but now with the promo the Senheiser is reasonable value for money. Atleast if you are thinking about giving this to your teenage kids.Fine with it. No complaints. Cause if you look at it in this way every 6months they will end up buying new cans. Cause the wires just snap but with the Senheiser you can easily replace them. All the parts sponge head sponge and the cables you can swap them when wear and tear approaches.Besides you only have 1pair of ears so either you take good care of them for the better part of your life or you end up loosing to be deaf as time and age passes by. Your choice. For me I will this model. It is fine for daily use.Reasonable.
Reviewer: pietro maria spadetta
Rating: 4.0 out of 5 stars
Title:
Review: Attenzione ho messo solo 4 stelle perche’………………..la confezione e’ veramente povera ed i fili non sembrano all’altezza del costo ma la cuffia suona molto bene e’ ben bilanciata su tutte le frequenze ha una buona stereofonia e localizzazione degli strumenti ed una ottima timbrica.In generale direi che e’ una cuffia da avere anche se probabilmente otterrete la stessa soddisfazione con cuffie da meno soldi ma se gia’ le avete prendete anche questa ,ha una timbrica tutta sua ma precisa e piacevole.